一种IP的获取方式
一般的来说,获取内网IP比较简单.
1 int main()
2 {
3 char hostname[ 128 ];
4 (gethostname(hostname, 128 ) == 0 ) ? NULL:MessageBox(NULL, " 无法获取网络地址 " ,hostname,MB_OK);
5 struct hostent * pHost = gethostbyname(hostname);
6 char * szLocalIP = new char [ sizeof (pHost)];
7 for ( int i = 0 ; pHost != NULL && pHost -> h_addr_list[i] != NULL; i ++ )
8 {
9 strcpy(szLocalIP,(inet_ntoa( * ( struct in_addr * )pHost -> h_addr_list[i])));
10 }
11 printf( " LocalIP : %s \n " ,szLocalIP);
12 return 0 ;
13 }
外网IP大多是去通过路由获得,不过我选择了一种相对简单的方式.
1 #include < stdio.h >
2 #include < Wininet.h >
3 #include < string .h >
4 #pragma comment(lib,"Wininet.lib")
5
6 char * GetPosString( char * str, int nBegin, int nEnd)
7 {
8 static char buff[ 1001 ] = { 0 };
9 int j = 0 ;
10 if (nBegin < strlen(str) && nBegin >= 0 && strlen(str) <= 1000 )
11 {
12 for ( int i = nBegin - 1 ;i <= nEnd - 1 ;i ++ )
13 {
14 buff[j] = str[i];
15 j ++ ;
16 }
17 buff[j] = ' \0 ' ;
18 }
19 return buff;
20 }
21
22 char * GetMarkString( char * str, char szBegin, char szEnd)
23 {
24 char * szOne = strchr(str,szBegin);
25 char * szTwo = strchr(str,szEnd);
26 int nBegin = szOne - str + 2 ; // 平时不+2,只是因为那个页面IP前有2个空格....
27 int nEnd = szTwo - str;
28 static char buff[ 1001 ] = { 0 };
29 int j = 0 ;
30 if (nBegin < strlen(str) && nBegin >= 0 && strlen(str) <= 1000 )
31 {
32 for ( int i = nBegin - 1 ;i <= nEnd - 1 ;i ++ )
33 {
34 buff[j] = str[i];
35 j ++ ;
36 }
37 buff[j] = ' \0 ' ;
38 }
39 return buff;
40 }
41
42 char * GetNetIP()
43 {
44 BOOL bResult = FALSE;
45 HINTERNET hInternet = InternetOpen( " CEHTTP " , INTERNET_OPEN_TYPE_DIRECT, NULL, NULL, NULL);
46 if (hInternet == NULL)
47 return " InternetOpen Error " ;
48 HINTERNET hSession = InternetConnect(hInternet, " www.ip138.com " , 80 , NULL, NULL, INTERNET_SERVICE_HTTP, 0 , 0 );
49 if (hSession == NULL)
50 return " InternetConnect Error " ;
51 char * szAccept[] = { " */* " , NULL};
52 HINTERNET hRequest = HttpOpenRequest(hSession, " GET " , " /ip2city.asp " ,
53 NULL, NULL, (LPCSTR * )szAccept, INTERNET_FLAG_NO_CACHE_WRITE, 0 );
54 if (hRequest == NULL)
55 return " HttpOpenRequest Error " ;
56 char headerLanguage[] = " Accept-Language: zh-cn\r\n " ;
57 char headerEncoding[] = " Accept-Encoding: gzip, deflate\r\n " ;
58 char headerContentType[] = " Content-Type: text/xml\r\n " ;
59
60 // 添加header 信息
61 // bResult = HttpAddRequestHeaders(hRequest, headerLanguage, -1, HTTP_ADDREQ_FLAG_ADD|HTTP_ADDREQ_FLAG_REPLACE);
62
63 if ( ! HttpSendRequest(hRequest,NULL, 0 ,NULL, 0 ))
64 return " HttpSendRequest Error " ;
65 TCHAR szBuf[ 256 ];
66 DWORD_PTR dwRet = - 1 ;
67
68 while (InternetReadFile(hRequest,szBuf, 256 , & dwRet) && dwRet != 0 )
69 {
70 OutputDebugString(szBuf);
71 }
72 char * szIP;
73 szIP = GetMarkString((( char * )szBuf), ' [ ' , ' ] ' );
74 return szIP;
75 }
76
77
78
79 int main()
80 {
81 printf( " NetIP : %s \n " ,GetNetIP());
82
83 return 0 ;
84 }
当然,你也许会说如果获取IP的页面失效怎么办.不过我想在自己的服务端多这么个页面应该不是什么问题吧. :)